RA Capital Nexus Fund III, L.P. is Director & 10% Owner at Sionna Therapeutics, Inc. (SION). They have made 4 open-market trades across 3 companies since 2023, most recently 2026-09-28.
CIK 0001883840
3 open-market purchases totalling $70.5M since 2023, against 1 sale. Too few scored purchases to measure a record yet.
| Ticker | Shares | Value |
|---|---|---|
| MLYS | 4,280,051 | $86.8M |
| BCAX | 2,500,095 | $41.9M |
| SION | 715,988 | $2.8M |
| CLYM | 70,000 | $687K |
| Total | $132.3M |
Shares reported on the most recent Form 4, priced at the 2026-09-30 close.
Counted per filing, not per execution lot — a purchase filled in several tranches is one decision.
Grouped by shared companies and similar filing behaviour. This is a similarity measure, not a ranking or a performance signal.